ML18199A322
| ML18199A322 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 07/18/2018 |
| From: | Samson Lee Plant Licensing Branch 1 |
| To: | Wells R Tennessee Valley Authority |
| References | |
| L-2018-LLA-0060 | |
| Download: ML18199A322 (5) | |
Text
NRR-DMPSPEm Resource From: Lee, Samson Sent: Wednesday, July 18, 2018 11:12 AM To: rdwells0@tva.gov Cc: Hon, Andrew
Subject:
final audit plan - Sequoyah Nuclear Plant, Units 1 and 2, Request to Modify Essential Raw Cooling Water Motor Control Center Breakers and to Revise the Updated Final Safety Analysis Report (SQN-TS-17-04) (EPID: L-2018-LLA-0060)
Attachments: final audit plan for Sequoyah Kirk Key LAR.docx Mr. Wells, Attached is final audit plan for the subject Sequoyah license amendment request. The only change from the 6/28/18 draft is the insertion of July 26 as the date of the entrance conference call.
- Thanks, Sam 1
Hearing Identifier: NRR_DMPS Email Number: 481 Mail Envelope Properties (Samson.Lee@nrc.gov20180718111100)
Subject:
final audit plan - Sequoyah Nuclear Plant, Units 1 and 2, Request to Modify Essential Raw Cooling Water Motor Control Center Breakers and to Revise the Updated Final Safety Analysis Report (SQN-TS-17-04) (EPID: L-2018-LLA-0060)
Sent Date: 7/18/2018 11:11:41 AM Received Date: 7/18/2018 11:11:00 AM From: Lee, Samson Created By: Samson.Lee@nrc.gov Recipients:
"Hon, Andrew" <Andrew.Hon@nrc.gov>
Tracking Status: None "rdwells0@tva.gov" <rdwells0@tva.gov>
Tracking Status: None Post Office:
Files Size Date & Time MESSAGE 226 7/18/2018 11:11:00 AM final audit plan for Sequoyah Kirk Key LAR.docx 30579 Options Priority: Standard Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:
Recipients Received:
7/18/2018 REGULATORY AUDIT PLAN FOR SEQUOYAH NUCLEAR PLANT, UNITS 1 AND 2 TO SUPPORT REVIEW OF THE LICENSE AMENDMENT REQUEST (LAR)
REGARDING REMOVAL OF KIRK KEY INTERLOCK FROM FEEDER BREAKERS AND TIE BREAKERS FOR ESSENTIAL RAW COOLING WATER MOTOR CONTROL CENTER DOCKET NOS. 50-327 AND 50-328 (EPID: L-2018-LLA-0060)
BACKGROUND By letter dated March 9, 2018 (Agencywide Document Access Management System (ADAMS)
Accession No. ML18071A349), as supplemented by letter dated April 11, 2018 (ADAMS Accession No. ML18102B430), Tennessee Valley Authority (TVA), the licensee for Sequoyah Nuclear Plant (SQN), Units 1 and 2, requested the U.S. Nuclear Regulatory Commission (NRC) staff approval to modify Essential Raw Cooling Water (ERCW) Motor Control Center (MCC)
Breakers and revise the Updated Final Safety Analysis Report (UFSAR) for SQN Units 1 and 2 to clarify the normal and alternate power supply for ERCW.
SQN has implemented a design change to remove the existing mechanical (Kirk Key) interlocking scheme from the feeder breakers and tie breakers for ERCW MCCs 1A-A and 2A-A. The physical control of the ERCW MCC feeder breakers was replaced with administrative (procedural) controls. In NRC Inspection Report 05000327/2015007 and 05000328/2015007, dated September 14, 2015 (ADAMS Accession No. ML15257A435), the NRC determined that this design change required prior NRC approval. By letter dated January 8, 2016 (ADAMS Accession No. ML16012A480), TVA provided observations on the basis for the non-cited violations. By letter dated March 9, 2018 (ADAMS Accession No. ML18071A349), TVA requested NRC approval to complete the implementation of the design change to remove the mechanical interlock device from the feeder breakers and tie breakers from the ERCW MCCs 1B-B and 2B-B and to revise the ERCW System Description in Section 9.2.2.2 of the SQN UFSAR for the ERCW system. This request would resolve the issues in NRC Inspection Report 05000327/2015007 and 05000328/2015007.
REGULATORY AUDIT BASIS A Regulatory Audit is a planned license or regulation-related activity that includes the examination and evaluation of primarily non-docketed information. A Regulatory Audit is conducted with the intent to gain understanding, to verify information and/or to identify information that will require docketing to support the basis for the licensing or regulatory decision.
INFORMATION NEEDS Information needed in the electrical engineering area:
- 2. Electrical Short Circuit Calculations related to the LAR
- 3. Electrical Protective Relay/Breaker coordination/setting calculations related to the LAR 1
- 4. Electrical Equipment Ratings related to the LAR (if not already covered as part of items 2 and 3 above)
Information needed in the human factors area:
- 1. The general deterministic review guidance in NUREG-1764 states that the licensee should provide adequate assurance that the change meets current regulations. Explain the effect on each of the safety-related power supplies (whether powered from normal or emergency power sources) for each unit if the administrative controls were to fail and both sources of power were aligned to any single ERCW MCC. For example, what is the effect on 6.9KV shutdown boards 1A-A and 2A-A and their emergency power supplies (the emergency diesel generators) if both the normal and alternate power supplies are aligned to ERCW 480V MCC 1A-A while the shutdown boards are being powered by their respective emergency power sources?
- 2. The general deterministic review guidance in NUREG-1764 states that the licensee should provide adequate assurance that the change does not compromise defense in depth. Describe how defense in depth is maintained (for both the ERCW and emergency power systems) when replacing the mechanical interlock with administrative controls.
- 3. The analysis review guidance in NUREG-1764 states that the licensee should perform a functional and task analysis to identify how personnel will know when the human action is necessary and has been performed correctly, provide a description of what personnel must do, and identify how the human tasks are being changed. Describe the procedures and administrative controls used to identify when it is acceptable to perform the actions, how to perform the required actions, and how the operator will know if the action has been performed correctly. Include descriptions of any procedural direction regarding when it is not appropriate to perform the action.
- 4. The analysis review guidance in NUREG-1764 states that the licensee should identify potential errors and their consequences. Describe any potential errors associated with the action and their consequences, including how any undesirable consequences (such as tripping an MCC due to aligning both power supplies) would be mitigated.
- 5. The human system interface (HSI), procedures, and training review guidance in NUREG-1764 states that the licensee should describe any known operating experience issues.
Describe any relevant operating experience related to failure of administrative controls or breaker manipulations and how that operator experience has been incorporated.
- 6. The HSI, procedures, and training review guidance in NUREG-1764 states that the licensee should describe any modifications to procedures and provide justification if no changes are made. Describe any changes to procedures other than those described in the LAR or in response to the questions above.
As necessary, please make available technical staff or contractors who are familiar with the information to assist the NRC staff during the audit.
Additional information needs identified during the audit will be communicated to the designated point of contact.
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TEAM ASSIGNMENTS/RESOURCE ESTIMATES The duration of this audit is consistent with the LAR review schedule of April 2018 to May 2019. The resource estimate for this audit is approximately 200 hours0.00231 days <br />0.0556 hours <br />3.306878e-4 weeks <br />7.61e-5 months <br /> of direct audit effort. The NRC staff performing this audit will include, but may not be limited to, the following staff:
AUDIT TEAM
- Andrew Hon, TVA Lead Project Manager, Plant Licensing Branch II-2, Division of Operating Reactor Licensing, NRR
- Samson Lee, Backup Project Manager, Division of Operating Reactor Licensing, NRR
- Vijay Goel, Electrical Engineering Technical Reviewer, Division of Engineering, NRR
- Gerard Purciarello, Plant Systems Technical Reviewer, Division of Safety Systems, NRR
- Michelle Kichline, Human Factors Technical Reviewer, Division of Risk Assessment, NRR
- Johnny Hughey, Human Factors Technical Reviewer, Division of Risk Assessment, NRR LOGISTICS The audit will start after the entrance phone call on July 26, 2018. Please provide electronics reading room with read-only access. Based on the need, the NRC staff will obtain clarification of the information by means such as phone calls, video conferencing, or site visits.
DELIVERABLES At the conclusion of the audit, the NRC staff will conduct an exit briefing and provide a summary of audit results. The NRC staff plans to prepare a Regulatory Audit summary within 90 days of the completion of the audit.
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